THE MEDUS. 135 
the form of a cross. The edges of the bell have a snowy fringe, 
which has a remarkably pretty effect. 
The acalephe are often found together in considerable numbers. 
' The barks which navigate Lake Thau meet at certain periods of 
the year with numerous colonies of a species about the size of a 
small melon, nearly transparent, whitish, like water mixed with a 
LIZZIA KG@:LLIKERI, MAGNIFIED. 
little aniseed. At first sight this floating colony might be taken 
for a collection of muslin bonnets scattered upon the water. 
The Liszia of Kolliker is so small that it can scarcely be re- 
cognised in transparent water, yet often on the coasts of Greenland 
large patches are seen coloured by this pretty brown medusa. A 
wine-glass of water can contain 3,000 of them. One of their banks, 
which seemed nothing in the expanse of the ocean, was calculated 
to contain 1,600,000,000,000,000 of these animalcules. What a 
